WO2018198799A1

WO2018198799A1 - Blower device

Info

Publication number: WO2018198799A1
Application number: PCT/JP2018/015397
Authority: WO
Inventors: 裕一佐久間; 大介小笠原; 村上　淳
Original assignee: 日本電産株式会社
Priority date: 2017-04-27
Filing date: 2018-04-12
Publication date: 2018-11-01
Also published as: CN110537026A

Abstract

In one embodiment of this blower device, an impeller has: an impeller hub; a plurality of axial flow blades extending radially outward from the outer peripheral surface of the impeller hub and arranged circumferentially side by side; and centrifugal blades which, on the front side, in a rotational direction, of the radially inner ends of the axial flow blades, connect to the radially inner ends of the axial flow blades. The outer peripheral surface of the impeller hub is a sloped surface having an outer diameter which increases from above downward. The upper surfaces of the centrifugal blades connect to the upper surfaces of the axial flow blades. The centrifugal blades have second blade surfaces connecting to the upper surfaces of the centrifugal blades and facing forward in the rotational direction. The second blade surfaces are sloped surfaces bending rearward in the rotational direction as the surfaces extend from the radially inner side toward the radially outer side. The radially outer ends of the second blade surfaces connect to the connection surfaces of a surface of the impeller, the connection surfaces extending downward from the radially inner ends of first blade surfaces.

Description

Blower

The present invention relates to a blower.

An axial fan motor that blows air in the axial direction of the rotation shaft of the impeller is known. For example, Patent Document 1 describes an axial fan motor in which coil windings are arranged to face a rotor magnet with a gap in the axial direction.

Japanese Publication No. 2006-233812

The axial fan motor as described above blows air by sending air located on one side in the axial direction of the impeller blade part to the other side in the axial direction by the impeller blade part. For this reason, the smaller the radial dimension of the impeller blade portion, the lower the amount of air that can be sent by the axial fan motor. Therefore, when the radial size of the impeller blade portion needs to be relatively small due to restrictions on the location where the axial fan motor is installed, the air flow rate of the axial fan motor may not be sufficiently obtained. It was.

In view of the above circumstances, an object of the present invention is to provide a blower that can improve the amount of blown air.

One aspect of the blower of the present invention includes an impeller that can rotate around a central axis that extends in the vertical direction, and a motor that rotates the impeller around the central axis, and the impeller has an outer periphery that extends in the axial direction. An impeller hub having a surface, a plurality of axial flow blade portions extending radially outward from the outer peripheral surface of the impeller hub and arranged side by side along the circumferential direction, and the axial flow blade portion provided on the outer peripheral surface of the impeller hub A centrifugal blade portion connected to the radially inner end portion of the axial flow blade portion on the front side in the rotational direction of the radially inner end portion, and the outer peripheral surface of the impeller hub is directed from the upper side to the lower side. It is an inclined surface with an outer diameter increasing, and the axial-flow blade portion has a first blade surface facing downward, and the first blade surface is lower as it goes from the front side in the rotational direction to the rear side in the rotational direction. Tilt located at And the upper surface of the centrifugal blade portion is connected to the upper surface of the axial flow blade portion, the centrifugal blade portion is connected to the upper surface of the centrifugal blade portion and has a second blade surface facing the front side in the rotation direction, The second blade surface is an inclined surface located on the rear side in the rotational direction as it goes from the radially inner side to the radially outer side, and the radially outer end of the second blade surface is a surface of the impeller. It connects with the connection surface extended below from the edge part of the radial direction inner side of a said 1st blade | wing surface.

According to one aspect of the present invention, a blower capable of improving the blown amount is provided.

FIG. 1 is a perspective view showing the blower of the first embodiment. FIG. 2 is a view showing the blower of the first embodiment and is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a diagram of the impeller according to the first embodiment viewed from above. FIG. 4 is a perspective view showing a part of the impeller of the first embodiment. FIG. 5 is a view of the impeller of the first embodiment as viewed along the radial direction. FIG. 6 is a perspective view showing a part of an impeller as another example of the first embodiment. FIG. 7 is a perspective view showing the blower of the second embodiment. FIG. 8 is a view of the impeller of the second embodiment as viewed from above. FIG. 9 is a view of a part of an impeller, which is another example of the second embodiment, viewed from above.

The Z-axis direction shown as appropriate in each drawing is a direction parallel to the vertical direction. The positive side in the Z-axis direction is “upper side”, and the negative side in the Z-axis direction is “lower side”. Further, the central axis J shown as appropriate in each drawing extends in the Z-axis direction, that is, the vertical direction. In the following description, the axial direction of the central axis J, that is, the vertical direction parallel to the Z-axis direction is simply referred to as “axial direction Z”. The radial direction centered on the central axis J is simply referred to as “radial direction”, and the circumferential direction centered on the central axis J is simply referred to as “circumferential direction θ”. The vertical direction, the upper side, and the lower side are simply names for explaining the relative positional relationship of each part, and the actual layout relationship is a layout relationship other than the layout relationship indicated by these names. May be.

<First Embodiment>
As shown in FIGS. 1 and 2, the blower 10 includes a motor support portion 40, a bearing 60, a housing 50, a motor 30, and an impeller 20 that can rotate around a central axis J.

The motor support unit 40 supports the motor 30. As shown in FIG. 2, the motor support portion 40 includes a stator support portion 41 and a bearing holding portion 42. The stator support portion 41 extends in the radial direction. Although not shown, the stator support portion 41 has a circular shape centered on the central axis J when viewed along the axial direction Z. The outer diameter of the stator support portion 41 increases from the upper side toward the lower side. That is, the outer peripheral surface 41a of the stator support portion 41 is an inclined surface whose outer diameter increases from the upper side to the lower side. The outer peripheral surface 41a of the stator support portion 41 is located on the radially outer side than the outer peripheral surface 21a of the impeller hub 21 described later. The bearing holding portion 42 has a cylindrical shape protruding upward from the upper surface of the stator support portion 41. More specifically, the bearing holding portion 42 has a cylindrical shape with the central axis J as the center and opening upward.

The bearing 60 is held inside the bearing holding portion 42. The bearing 60 extends in the axial direction Z and has a cylindrical shape centered on the central axis J. The outer peripheral surface of the bearing 60 is fixed to the inner peripheral surface of the bearing holding portion 42. The bearing 60 is, for example, a slide bearing.

The housing 50 is disposed on the radially outer side than the motor support portion 40. As shown in FIG. 1, the housing 50 has a rectangular tube shape extending in the axial direction Z. The outer shape of the housing 50 is a rounded square shape when viewed from above. As shown in FIG. 2, the housing 50 surrounds the impeller 20 and the motor 30 in the circumferential direction θ from the radially outer side. In the present embodiment, the housing 50 includes two members: an upper housing 51 and a lower housing 52 fixed to the upper housing 51 below the upper housing 51. Although illustration is omitted, the inner peripheral surface of the lower housing 52 and the outer peripheral surface 41a of the stator support portion 41 are connected by a plurality of ribs.

The motor 30 includes a shaft 31, a rotor core 32, a magnet 33, and a stator 34. The shaft 31 has a cylindrical shape extending in the axial direction Z with the central axis J as the center. A lower portion of the shaft 31 is rotatably supported by the bearing 60. The rotor core 32 has an annular plate shape centered on the central axis J. The rotor core 32 is fixed to the bottom surface of an accommodation recess 21d provided on the lower surface of the impeller hub 21, which will be described later. The magnet 33 has an annular plate shape centered on the central axis J. The magnet 33 is fixed to the lower surface of the rotor core 32. Thereby, the magnet 33 is fixed to the impeller hub 21. The lower surface of the magnet 33 and the lower surface of the impeller hub 21 are arranged on the same plane orthogonal to the axial direction Z.

The stator 34 has an annular plate shape centered on the central axis J. The stator 34 is fixed to the upper surface of the stator support portion 41. A bearing holding portion 42 is located inside the stator 34 in the radial direction. The stator 34 faces the magnet 33 in the axial direction Z with a gap on the lower side of the magnet 33. That is, in this embodiment, the motor 30 is an axial gap type motor. The stator 34 includes a substrate 34a and a coil 34b. The coil 34b is configured by, for example, a wiring pattern printed on the substrate 34a. The coil 34b is centered on an axis extending in the axial direction Z. A plurality of the coils 34b are arranged along the circumferential direction θ.

2 and 3, the impeller 20 includes an impeller hub 21, a plurality of axial flow blade portions 22, a connection portion 24, and a centrifugal blade portion 23. As shown in FIG. 2, the impeller hub 21 has an outer peripheral surface 21 a extending in the axial direction Z. The impeller hub 21 has a flat, substantially truncated cone shape centered on the central axis J. The outer diameter of the impeller hub 21 increases from the upper side toward the lower side. That is, the outer peripheral surface 21a of the impeller hub 21 is an inclined surface whose outer diameter increases from the upper side to the lower side. The inclination of the outer peripheral surface 21a of the impeller hub 21 with respect to the axial direction Z is larger than the inclination of the outer peripheral surface 41a of the stator support portion 41 with respect to the axial direction Z. The lower end portion of the outer peripheral surface 21 a of the impeller hub 21 is disposed at substantially the same position in the radial direction as the upper end portion of the outer peripheral surface 41 a of the stator support portion 41. The radially outer edge at the upper end of the impeller hub 21 is rounded. Thereby, the upper surface 21e and the outer peripheral surface 21a of the impeller hub 21 are smoothly connected. The upper surface 21e is a flat surface orthogonal to the axial direction Z.

The impeller hub 21 has a recess 21 b that is recessed upward from the lower surface of the impeller hub 21. The outer shape viewed from the lower side of the recess 21b is a circular shape centered on the central axis J. The upper end portion of the bearing holding portion 42 is inserted into the concave portion 21b. The impeller hub 21 has an accommodating recess 21d that is recessed upward from the lower surface of the impeller hub 21 on the radially outer side of the recess 21b. The housing recess 21d has an annular shape centered on the central axis J. The housing recess 21d surrounds the recess 21b. The housing recess 21d houses and holds the rotor core 32 and the magnet 33.

The impeller hub 21 has a fixing hole 21c penetrating in the axial direction Z from the bottom surface of the recess 21b to the upper surface 21e of the impeller hub 21. The upper end portion of the shaft 31 is fitted and fixed to the fixing hole portion 21c. The upper end surface of the shaft 31 and the upper surface 21e of the impeller hub 21 are arranged on the same plane orthogonal to the axial direction Z.

In the present embodiment, the impeller hub 21, the shaft 31, the rotor core 32, and the magnet 33 constitute a rotor of the motor 30 that rotates around the central axis J. As a result, the motor 30 can rotate the impeller hub 21 as a part of the rotor and rotate the impeller 20 around the central axis J.

In the present embodiment, the motor 30 rotates the impeller 20 in a positive direction in the circumferential direction θ, that is, in a counterclockwise direction when viewed from the upper side to the lower side. The positive side in the circumferential direction θ, that is, the side proceeding counterclockwise when viewed from the upper side to the lower side is referred to as the front side in the rotational direction. The negative side in the circumferential direction θ, that is, the side proceeding clockwise as viewed from the upper side to the lower side is referred to as the rear side in the rotational direction.

As shown in FIG. 3, the plurality of axial flow blade portions 22 extend radially outward from the outer peripheral surface 21a of the impeller hub 21 and are arranged side by side along the circumferential direction θ. The plurality of axial flow blade portions 22 are arranged at equal intervals over the entire circumference along the circumferential direction θ. In FIG. 3, nine axial flow blade portions 22 are provided, for example. The axial-flow blade | wing part 22 is located in the rotation direction front side as it goes to a radial direction outer side from a radial direction inner side. That is, the axial flow blade portion 22 has a forward blade shape having a forward angle. Therefore, noise generated when the impeller 20 rotates can be reduced.

As shown in FIG. 4, the lower surface of the axial flow blade portion 22 is a first blade surface 22a facing downward. That is, the axial flow blade portion 22 has a first blade surface 22a. As shown in FIG. 5, the first blade surface 22 a is an inclined surface that is located on the lower side from the front side in the rotational direction toward the rear side in the rotational direction. In the present embodiment, the first blade surface 22a is a curved surface whose inclination with respect to a surface orthogonal to the axial direction Z increases as it goes from the front side in the rotational direction to the rear side in the rotational direction. An end of the first blade surface 22a on the front side in the rotational direction is disposed below the upper surface 21e of the impeller hub 21. The end of the first blade surface 22a on the rear side in the rotation direction is disposed at the same position in the axial direction Z as the lower surface of the impeller hub 21.

As shown in FIGS. 1 and 3, the upper surface of the axial flow blade portion 22 has a flat portion 22c and a curved portion 22b. The flat portion 22c is a flat portion orthogonal to the axial direction Z. The end portion on the front side in the rotation direction of the flat portion 22 c is the end portion on the front side in the rotation direction of the upper surface of the axial flow blade portion 22. The flat portion 22 c is disposed below the upper surface 21 e of the impeller hub 21.

The curved portion 22b is connected to the end of the flat portion 22c on the rear side in the rotational direction. As shown in FIG. 5, the bending portion 22b is an inclined surface that is located on the lower side from the front side in the rotational direction toward the rear side in the rotational direction, and the inclination with respect to the plane orthogonal to the axial direction Z rotates from the front side in the rotational direction. It is a curved surface that becomes larger toward the rear side in the direction.

As shown in FIG. 2, the connecting portion 24 protrudes radially outward from the outer peripheral surface 21 a of the impeller hub 21. The connection part 24 is disposed below the axial flow blade part 22. More specifically, the connecting portion 24 is disposed below the end portion on the radially inner side of the axial flow blade portion 22. The upper end portion of the connecting portion 24 is connected to the radially inner end portion of the axial flow blade portion 22. A radially outer surface of the connection portion 24 is a connection surface 24a. The connection surface 24a is a surface that extends downward from the radially inner end of the first blade surface 22a among the surfaces of the impeller 20. The lower end of the connection surface 24a is disposed at the same position as the lower surface of the impeller hub 21 in the axial direction Z. As shown in FIG. 4, the connection surface 24 a is a curved surface extending along the circumferential direction θ. The connection surface 24a is orthogonal to the radial direction. A plurality of connection portions 24 are provided and provided for each of the plurality of axial flow blade portions 22.

When the outer peripheral surface of the impeller hub is an inclined surface as in the present embodiment, when an impeller is manufactured by injection molding using a mold, the radially inner end of the axial flow blade portion is difficult to be removed from the mold, and the impeller May be difficult to manufacture. On the other hand, according to the present embodiment, the impeller 20 is divided into two molds divided in the axial direction Z by providing the connecting portion 24 protruding radially outward from the outer peripheral surface 21a of the impeller hub 21. When manufacturing by injection molding that pours in, the impeller 20 molded from the lower mold can be easily pulled out. Therefore, the impeller 20 can be easily manufactured using a mold.

The centrifugal blade portion 23 is provided on the outer peripheral surface 21 a of the impeller hub 21. The centrifugal blade portion 23 protrudes radially outward from the outer peripheral surface 21 a of the impeller hub 21. The centrifugal blade portion 23 is connected to the radially inner end portion of the axial flow blade portion 22 on the front side in the rotational direction of the radially inner end portion of the axial flow blade portion 22. The upper surface 23 a of the centrifugal blade portion 23 is connected to the upper surface of the axial flow blade portion 22. More specifically, the end on the rear side in the rotation direction of the upper surface 23a is connected to the end on the radially inner side of the flat portion 22c. The upper surface 23a and the flat portion 22c are arranged on the same plane orthogonal to the axial direction Z. The shape of the upper surface 23a viewed from above is a triangular shape.

The centrifugal blade portion 23 has a second blade surface 23b. The second blade surface 23b is a surface that is connected to the upper surface 23a of the centrifugal blade portion 23 and faces the front side in the rotation direction. In the present embodiment, the second blade surface 23b extends downward from one radial outer side of the upper surface 23a. The second blade surface 23b is an inclined surface located on the rear side in the rotational direction as it goes from the radially inner side to the radially outer side. That is, the second blade surface 23b has a receding angle. Thus, the second blade surface 23b faces the front side in the rotational direction and faces the radially outer side. In the present embodiment, the second blade surface 23b is a flat surface parallel to the axial direction Z.

When viewed along a direction orthogonal to the second blade surface 23b, the second blade surface 23b has a substantially right triangle shape. The second blade surface 23b includes an upper side 23c along the upper end of the second blade surface 23b, a connection side 23d extending downward from a radially outer end of the upper side 23c, and a radially inner side of the upper side 23c. And a hypotenuse 23e that connects the end and the lower end of the connecting side 23d. The upper side 23c is orthogonal to the axial direction Z. The connection side 23d is parallel to the axial direction Z. The oblique side 23e is disposed on the outer peripheral surface 21a. The dimension in the axial direction Z of the second blade surface 23b increases from the radially inner side toward the radially outer side. The lower end portion of the second blade surface 23 b is connected to the lower end portion of the impeller hub 21. The lower end of the second blade surface 23b is an intersection of the connection side 23d and the oblique side 23e.

As shown in FIG. 3, the radially inner end of the second blade surface 23b is connected to the rotational direction rear end of the curved portion 22b of the axial flow blade 22 adjacent to the rotational direction front side and the circumferential direction θ. At approximately the same position. As shown in FIG. 4, the radially outer end of the second blade surface 23b is connected to the connection surface 24a. Thereby, the centrifugal blade part 23 is connected to the axial flow blade part 22 and the connection part 24. As shown in FIG. 5, the radially outer end portion of the second blade surface 23b is arranged on the rear side in the rotational direction with respect to the end portion on the rear side in the rotational direction of the first blade surface 22a. In the present embodiment, the radially outer end of the second blade surface 23b is a connection side 23d. A plurality of centrifugal blade portions 23 are provided and provided for each of the plurality of axial flow blade portions 22.

The material of the impeller 20 is not particularly limited, and is, for example, resin. The impeller 20 is manufactured as a single member by, for example, injection molding using a mold.

The blower 10 of the present embodiment is a relatively thin blower that employs an axial gap type motor as the motor 30. The ratio of the dimension in the axial direction Z of the blower 10 to the dimension in the direction orthogonal to the axial direction Z of the blower 10 is preferably smaller than 0.25 and 0.2 or less. The dimension in the direction orthogonal to the axial direction Z of the blower 10 is, for example, the length of one side of the outer shape of the housing 50 when viewed from above, and is the horizontal dimension of the blower 10 in FIG. The dimension of the blower 10 in the axial direction Z is, for example, the dimension of the housing 50 in the axial direction Z.

When the impeller 20 is rotated by the motor 30, the axial flow blade portion 22 advances forward in the rotational direction. Here, the 1st blade surface 22a which the axial flow blade part 22 has is an inclined surface located in the lower side as it goes to the rotation direction rear side from the rotation direction front side. Therefore, when the first blade surface 22a moves forward in the rotation direction along with the rotation of the axial flow blade portion 22, the air located on the front side in the rotation direction of the first blade surface 22a is along the first blade surface 22a. Sent to the bottom. Thereby, when the impeller 20 rotates and the axial flow blade portion 22 rotates, an air flow AF1 flowing from the upper side of the impeller 20 to the lower side of the impeller 20 is generated as shown in FIG. The air flow AF <b> 1 is a flow of air that is generated when air positioned above the axial flow blade portion 22 is sent to the lower side of the axial flow blade portion 22 by the axial flow blade portion 22.

On the other hand, when the centrifugal blade portion 23 moves forward in the rotational direction by the rotation of the impeller 20, the air located in the rotational direction forward side of the second blade surface 23b is radially outward along the second blade surface 23b by the centrifugal force. Sent to. The air located on the front side in the rotation direction of the second blade surface 23b is sent to the outside in the radial direction, so that the air located on the upper side of the impeller hub 21 is drawn into the front side in the rotation direction of the second blade surface 23b. Sent to the outside.

The air sent radially outward along the second blade surface 23b is connected to the connecting surface 24a at the radially outer end of the second blade surface 23b, and as shown in FIG. 4, the first blade surface 22a. Sent to the front side in the direction of rotation. Thereby, the air sent to the radial direction outer side along the 2nd blade surface 23b can be sent to the lower side of the impeller 20 by the 1st blade surface 22a. As described above, as shown in FIGS. 2 and 4, the air flow AF <b> 2 that is drawn radially outward from the upper side of the impeller hub 21 and flows to the lower side of the impeller 20 along the second blade surface 23 b and the first blade surface 22 a in order. Occurs.

As described above, in the blower device 10 of the present embodiment, by providing the axial flow blade portion 22 and the centrifugal blade portion 23, the air obtained by adding the air flow AF1 and the air flow AF2 can be sent in the axial direction Z. . Here, in the case where the centrifugal blade portion 23 is not provided, the air sent by the blower is only the air by the air flow AF1 generated only by the axial flow blade portion 22. On the other hand, according to the present embodiment, in addition to the air flow AF1, since the air flow AF2 can be generated by the centrifugal blade portion 23 and the axial flow blade portion 22, the amount of air sent by the blower 10 Can do more. Therefore, the air blower of this embodiment can improve the air flow rate of the air blower 10 without enlarging the radial dimension of the axial flow blade part 22. Moreover, the air blower of this embodiment can improve the static pressure of air by sending air to radial direction outer side by the centrifugal blade part 23. FIG. Thereby, the static pressure of the air sent by the air blower 10 can be improved.

Here, when the motor for rotating the impeller is an axial gap type motor as in this embodiment, it is necessary to enlarge the magnet in the radial direction in order to obtain the rotational torque of the motor. For this reason, the impeller hub to which the magnet is fixed is likely to be enlarged in the radial direction, and the radial dimension of the axial flow blade portion is likely to be relatively reduced. When the radial dimension of the axial flow vane portion is reduced, the amount of air sent by the axial flow vane portion is reduced. Therefore, when the impeller is rotated using an axial gap type motor, there is a problem that the air blowing amount of the blower tends to be small. Therefore, the above-described effect of improving the blown air volume is particularly useful when the motor of the blower is an axial gap type motor. Moreover, the air blower 10 can be easily thinned in the axial direction Z by using the motor 30 as an axial gap type motor.

Moreover, according to this embodiment, the outer peripheral surface 21a of the impeller hub 21 is an inclined surface whose outer diameter increases from the upper side toward the lower side. Therefore, it is easy to send the air located above the impeller hub 21 to the radially outer side and the lower side along the outer peripheral surface 21a. Thereby, it is easy to generate the air flow AF2 smoothly, and it is easy to reduce the loss of air. Therefore, it is possible to further improve the amount of air blown from the blower 10. Moreover, since the flow of the air flow AF2 can be made smooth, noise generated by the air flow AF2 can be reduced.

Further, according to the present embodiment, the outer peripheral surface 41 a of the stator support portion 41 is an inclined surface having an outer diameter that increases from the upper side to the lower side, and more radially outward than the outer peripheral surface 21 a of the impeller hub 21. Be placed. Therefore, the air sent to the lower side of the impeller 20 while proceeding radially outward and downward along the outer peripheral surface 21 a of the impeller hub 21 is radially outward and downward along the outer peripheral surface 41 a of the stator support portion 41. Sent. Thereby, the air discharged | emitted from the lower end part of the outer peripheral surface 41a to the lower side of the air blower 10 along the outer peripheral surface 41a progresses in the direction which leaves | separates from the outer peripheral surface 41a to the lower side, and leaves radially outside. Therefore, when the air along the outer peripheral surface 41a is released to the lower side of the blower device 10, it is easy to peel off from the outer peripheral surface 41a, and the blowing efficiency of the blower device 10 can be improved.

Further, according to the present embodiment, the second blade surface 23b is an inclined surface that is located on the rear side in the rotational direction from the radially inner side toward the radially outer side. Thereby, it is easy to guide the air flowing along the second blade surface 23 b to the axial flow blade portion 22 disposed on the rear side in the rotation direction of the centrifugal blade portion 23. In addition, the air sent radially outward along the second blade surface 23b is less likely to be disturbed, and noise generated by the airflow AF2 can be further reduced.

In addition, according to the present embodiment, the lower end portion of the second blade surface 23b is connected to the lower end portion of the impeller hub 21, so that the dimension in the axial direction Z of the second blade surface 23b is increased, It is easy to increase the area of the second blade surface 23b. Thereby, the quantity of the air sent to radial direction outer side by the 2nd blade surface 23b can be increased more. Therefore, it is possible to further improve the amount of air blown from the blower 10.

The present invention is not limited to the above-described embodiment, and other configurations can be adopted. In the following description, the same configurations as those in the above embodiment may be omitted by appropriately attaching the same reference numerals.

The second blade surface 23b may be configured like the second blade surface 123b shown in FIG. In the impeller 120 of the blower 110 illustrated in FIG. 6, the second blade surface 123 b is an inclined surface that is located radially inward from the lower side toward the upper side. That is, the second blade surface 123b faces the front side in the rotational direction and the radially outer side, and faces the upper side. Therefore, the air on the upper side of the impeller 120 is easily guided to the second blade surface 123b, and the second blade surface 123b makes it easier to send air to the front side in the rotation direction of the first blade surface 22a. Thereby, the ventilation volume of the air blower 110 can be improved more. Moreover, since the centrifugal blade part 123 can be made into a shape having a tapered shape, the centrifugal blade part 123 can be easily extracted from the mold when the impeller 120 is manufactured by injection molding using a mold. Therefore, the impeller 120 can be easily manufactured.

Second Embodiment
As shown in FIGS. 7 and 8, the centrifugal blade portion 223 extends in the circumferential direction θ in the impeller 220 of the blower 210 of the present embodiment. An end portion on the front side in the rotational direction of the centrifugal blade portion 223 is positioned on the front side in the rotational direction with respect to a radially inner end portion of the axial flow blade portion 22 adjacent to the front side in the rotational direction. In the present embodiment, the end portion on the front side in the rotation direction of the centrifugal blade portion 223 is located on the front side in the rotation direction with respect to the entire axial flow blade portion 22 adjacent to the front side in the rotation direction.

As shown in FIG. 8, when viewed along the axial direction Z, the centrifugal blade portions 223 adjacent to each other in the circumferential direction θ partially overlap in the radial direction. Therefore, the dimension of the circumferential direction θ of the second blade surface 223b can be increased, and the area of the second blade surface 223b can be increased. Thereby, the quantity of the air sent to radial direction outer side by the 2nd blade surface 223b can be increased more. Therefore, it is possible to further improve the amount of air blown by the blower 210.

The second blade surface 223b extends in the circumferential direction θ. In the present embodiment, the end portion of the second blade surface 223b on the front side in the rotation direction is located on the front side in the rotation direction with respect to the entire axial flow blade portion 22 adjacent on the front side in the rotation direction. The end of the second blade surface 223b on the front side in the rotational direction is connected to the upper surface 21e of the impeller hub 21. The second blade surface 223b is parallel to the axial direction Z. The second blade surface 223b is a curved surface that curves in a direction that swells radially outward.

The upper surface 223a of the centrifugal blade part 223 extends in the circumferential direction θ. The upper surface 223a is located on the lower side from the front side in the rotational direction toward the rear side in the rotational direction. Therefore, it is easy to send the air above the upper surface 223a to the rear side in the rotational direction along the upper surface 223a. The air sent to the rear side in the rotational direction along the upper surface 223a travels on the first blade surface 22a of the axial flow blade portion 22 adjacent to the rear side in the rotational direction along the upper surface of the axial flow blade portion 22 connected to the upper surface 223a. It is sent to the front side in the rotational direction. Thereby, it is easy to efficiently send air to the front side in the rotational direction of the axial flow blade portion 22, and the amount of air blown by the blower 210 can be further improved. An end portion of the upper surface 223a on the front side in the rotation direction is connected to a radially outer edge portion of the upper surface 21e of the impeller hub 21. The end of the upper surface 223a on the rear side in the rotation direction is connected to the flat portion 22c.

Note that the second blade surface 223b of the present embodiment may have a configuration like the second blade surface 323b shown in FIG. In the impeller 320 of the blower 310 shown in FIG. 9, the radially outer end of the second blade surface 323b is curved toward the rear side in the rotational direction, and is smoothly connected to the connection surface 24a. Therefore, air can be smoothly guided from the second blade surface 323b to the connection surface 24a. Thereby, it can suppress that air is disturb | confused in the connection part of the 2nd blade | wing surface 323b and the connection surface 24a, and the loss of the air sent by the centrifugal blade part 323 can be reduced. Therefore, the air volume of the air blower 310 can be further improved. Further, noise generated by the air flow can be reduced. The end of the second blade surface 323b on the outer side in the radial direction becomes smaller as the inclination with respect to the circumferential direction θ goes toward the outer side in the radial direction.

In each embodiment described above, the connection surface of the connection portion may be an inclined surface inclined with respect to the axial direction Z. Moreover, the connection part does not need to be provided. In this case, a part of the outer peripheral surface of the impeller hub corresponds to the connection surface. Further, the first axial flow blade portion may have a receding blade shape having a receding angle. In this case, a 1st axial flow blade | wing part is located in the rotation direction back side as it goes to a radial direction outer side from a radial direction inner side.

In each embodiment described above, the motor is an axial gap type motor, but is not limited thereto. The type of motor is not particularly limited, and the motor may be, for example, a radial gap type motor.

Moreover, the use of the air blower of each embodiment mentioned above is not specifically limited. The above-described configurations can be appropriately combined within a range that does not contradict each other.

DESCRIPTION OF SYMBOLS 10,110,210,310 ... Air blower, 20,120,220,320 ... Impeller, 21 ... Impeller hub, 21a ... Outer peripheral surface, 22 ... Axial flow blade part, 22a ... First blade surface, 23, 123, 223 323: Centrifugal blade portion, 23b, 123b, 223b, 323b ... Second blade surface, 24 ... Connection portion, 24a ... Connection surface, 30 ... Motor, 33 ... Magnet, 34 ... Stator, J ... Central axis, Z ... Axial direction , Θ ... Circumferential direction

Claims

A blower,
An impeller rotatable around a central axis extending in the vertical direction;
A motor for rotating the impeller around the central axis;
With
The impeller is
An impeller hub having an outer peripheral surface extending in the axial direction;
A plurality of axial flow blade portions extending radially outward from the outer peripheral surface of the impeller hub and arranged side by side along the circumferential direction;
A centrifugal blade portion provided on an outer peripheral surface of the impeller hub and connected to a radially inner end portion of the axial flow blade portion on a rotation direction front side of a radially inner end portion of the axial flow blade portion;
Have
The outer peripheral surface of the impeller hub is an inclined surface whose outer diameter increases from the upper side toward the lower side,
The axial flow blade portion has a first blade surface facing downward,
The first blade surface is an inclined surface located on the lower side from the front side in the rotational direction toward the rear side in the rotational direction,
The upper surface of the centrifugal blade portion is connected to the upper surface of the axial flow blade portion,
The centrifugal blade portion has a second blade surface that is connected to the upper surface of the centrifugal blade portion and faces the front side in the rotation direction,
The second blade surface is an inclined surface located on the rear side in the rotational direction as it goes from the radially inner side to the radially outer side,
The radially outer end of the second blade surface is connected to a connecting surface extending downward from the radially inner end of the first blade surface among the surfaces of the impeller.
The blower according to claim 1, wherein the lower end of the second blade surface is connected to the lower end of the impeller hub.
The impeller has a connecting portion that protrudes radially outward from the outer peripheral surface of the impeller hub,
The connecting portion is disposed below the axial flow blade portion,
The blower according to claim 1, wherein a radially outer surface of the connection portion is the connection surface.
The centrifugal blade portion extends in the circumferential direction, and is provided for each of the axial flow blade portions,
The blower device according to claim 1, wherein the centrifugal blade portions adjacent in the circumferential direction as viewed along the axial direction partially overlap in the radial direction.
The blower device according to claim 1, wherein an upper surface of the centrifugal blade portion extends in a circumferential direction and is located on a lower side from the front side in the rotation direction toward the rear side in the rotation direction.
The connection surface extends along a circumferential direction,
The air blower according to claim 1, wherein an end portion on the radially outer side of the second blade surface is curved toward the rear side in the rotation direction and smoothly connected to the connection surface.
The air blower according to claim 1, wherein the second blade surface is an inclined surface positioned radially inward from the lower side toward the upper side.
The blower according to claim 1, wherein the axial-flow blade portion is positioned on the front side in the rotational direction from the radially inner side toward the radially outer side.
The motor is
A magnet fixed to the impeller hub;
On the lower side of the magnet, a stator facing the magnet with a gap in the axial direction;
The air blower according to claim 1, comprising: